[Info-vax] What is the correct way to contact VSI?

[Arne Vajhøj]

On 11/26/2019 8:20 AM, Simon Clubley wrote:
> On 2019-11-25, Arne Vajhøj <arne at vajhoej.dk> wrote:
>> On 11/25/2019 1:17 PM, Simon Clubley wrote:
>>> On 2019-11-25, Phillip Helbig (undress to reply) <helbig at asclothestro.multivax.de> wrote:
>>>> Probably.  Be happy they didn't drop the SMTP connection, preventing the
>>>> email from being delivered at all.
>>>
>>> No, dropping the connection with a reject status is _exactly_ what
>>> should have happened, especially if it was a blacklisting issue,
>>> so that Mark would have been told immediately his email had not been
>>> delivered instead of him having to wonder if anyone at VSI was ever
>>> going to get back to him.
>>
>> 30 years ago email may have been directly from sender to
>> recipient, which mean that SMTP reject works.
>>
>> But today email will often go through many SMTP servers
>> and if the fifth out of eight has a spam filter that
>> doesn't like the email then sender would not see
>> the reject.
> 
> Are you sure about that Arne ?
> 
> There's a difference between routing email within a large organisation
> and dropping suspect mail with a SMTP reject while it is being received
> by the machines listed in the MX records for the receiving domain.
> 
> If it gets dropped at the MX boundary between the sending and receiving
> organisations, surely the email sender gets to find out directly because
> of the SMTP reject.

Am I sure that emails today usually makes multiple hops: yes.

Am I sure that intermediate email servers may have a spam filter: yes.

Do I know what percentage has such a config: no.

It is over 20 years since I last operated a mail server, so
I am not current on best practice. But based in my general
knowledge I would not run the spam filter on the first node
in the org receiving the email - that should be a passthrough
with no logic in DMZ.

But even if it were the first at receiver then there is still
the possibility that there are multiple servers at the sender
side.

Arne